Evaluating the persistence of large choroidal hypertransmission defects using SS-OCT imaging

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Large choroidal hypertransmission defects (hyperTDs), defined as bright lesions ≥250 μm on en face OCT, arise from retinal pigment epithelium (RPE) attenuation or loss in age-related macular degeneration (AMD).
• Previous research indicated that larger hyperTDs tend to persist, unlike smaller, transient lesions, marking a critical stage in AMD progression.

Purpose of the Study:

• To confirm the persistence of large choroidal hyperTDs in age-related macular degeneration (AMD).
• To evaluate the potential of large hyperTDs as a clinical trial endpoint for therapies targeting AMD progression.

Main Methods:

• Analysis of an independent dataset from a prospective swept-source OCT (SS-OCT) natural history study of AMD eyes.
• Identification and tracking of large choroidal hyperTDs (≥250 μm GLD) in 202 eyes (1725 hyperTDs) over an average of 46.6 months.

Main Results:

• Overwhelming persistence of large hyperTDs was observed, with 1718 out of 1725 (99.6%) persisting.
• Only 7 large hyperTDs (0.4%) were non-persistent, with an average baseline greatest linear dimension (GLD) of 385 μm.
• Non-persistence was often associated with the accumulation of hyperreflective material, presumed to be aggregated RPE cells, over the hyperTD site.

Conclusions:

• Large choroidal hyperTDs demonstrate remarkable persistence in AMD, reinforcing their role as a significant indicator of disease progression.
• The high persistence rate supports the utility of large hyperTDs as a reliable endpoint for clinical trials investigating interventions for intermediate to late-stage AMD.